<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>hello</title>
    <script src="js/jquery-2.1.1.js"></script>
</head>
<body>

<button id="start">start</button>
<script type="text/javascript">
    $('#start').on('click',function(){
       console.log('click start')
    });
</script>
<!--测试以下代码:在chrome的console中-->
<!--$._data($('#start').get(0),"events").click[0].handler;-->
</body>
</html>